Three Boy Scouts dug out chunks of a 190 million-year-old set of dinosaur tracks and threw the rocks into a reservoir, irreparably damaging the prehistoric find, a park ranger said.

The vandalism occurred during a Scout troop's outing at Red Fleet State Park in eastern Utah last week. About 300 dinosaur tracks are preserved in beds of sandstone at the park near Vernal.

Kay Godfrey, information officer for Great Salt Lake Council of the Boy Scouts of America, said the Scouts take responsibility for the incident and may review their policies to avoid vandalism in the future.

"This reflects a disregard for the principles that Scouting promotes," Godfrey said.

Park Ranger Curt Sinclear issued a juvenile citation for defacing natural resources after witnessing the incident July 19. The names of the three boys, all 15, and the Scout troop's number were not released.

State and local authorities are still reviewing jurisdiction in the case. There has been no decision on charging the boys.